ABSTRACT
Since the first recognition and description of sleep apnea in 1965 (23,24), crucial clinical and laboratory studies on sleep apnea have added new facets to our understanding of the physiological effects of sleep apnea on humans. The effects of sleep apnea on sleep, the daytime consequences that follow, and the clinical impact of this condition on human life may be far more profound than we can currently fathom. Patients with this condition may present with a variable combination of clinical symptoms affecting both sleep and daytime functions: the former tend to be more specific for sleep apnea while the latter are usually the nonspecific results of abnormal sleep regardless of the cause. To understand the impact of sleep apnea on wakefulness, it would be pertinent to first examine the respiratory physiology during normal sleep, the arousal responses to respiratory alterations during sleep, the effects of sleep apnea on sleep architecture, and the effect of sleep fragmentation on wakefulness.
